Identifying the MX-5050B
In the line-up↑ TOP
Two-channel MX-5050B with its black lower amplifier faceplate and two VU meters beneath the upright transport, photographed for Otari's 1979 brochure.
The 1979 B brochure pictures a two-channel example. Its black lower faceplate and touching record-ready buttons are useful clues; the photograph does not establish the suffix or the four-track layout.
How to recognise one↑ TOP
- Upright or flat. Otari's 1979 brochure gives the operating position as "vertical or horizontal" (1979 B brochure, Physical).
- Belt or no belt — the D decides. The maintenance manual splits the line in two: a "dc servo version" — the 2HD, 2LD, 4LD, FHD and FLD — and a "synchronous version" — the 2H, 2L and 4L (OS2-004, p.83, Parts List 13 note). The synchronous machines drive the capstan flywheel by belt from a pulley on the motor; the D models have a direct-drive capstan and change speed with a switch (OS2-004, sections 2-4 and 2-6).
- No 4H. The four-track B comes only as the 4L and 4LD: the manual's speed-conversion parts table lists the 2H at 15 and 7½ ips and the 2L and 4L at 7½ and 3¾ ips, and no 4H or 4HD appears anywhere in it (OS2-004, Table 2-2).
Read the rear plate↑ TOP
| Machine | Plate reads | Suffix | Format |
|---|---|---|---|
| B-2 | MX-5050B-2H | 15 & 7½ ips | ¼″ 2-channel |
| MX-5050B-2L | 7½ & 3¾ ips | ||
| MX-5050B-2HD | 15 & 7½ ips · DC servo | ||
| MX-5050B-2LD | 7½ & 3¾ ips · DC servo | ||
| B-4 | MX-5050B-4L | 7½ & 3¾ ips | ¼″ four-track — channel count unconfirmed |
| MX-5050B-4LD | 7½ & 3¾ ips · DC servo | ||
| B-F | MX-5050B-FHD | 15 & 7½ ips · DC servo | ¼″ full-track mono, DC servo only |
| MX-5050B-FLD | 7½ & 3¾ ips · DC servo |
The suffixes do not give the B-4's channel count, and nor does any Otari paper found so far: the 4L and 4LD's channels are never printed.
When it was sold↑ TOP
By 1978. Otari's own ads for the "all-new MX-5050-B" run from August 1978 in the US, at $1,795 (Recording Engineer/Producer, August 1978), and from October 1978 in the UK. The earliest dated B brochure, form 107-9-79, came later: it is "effective September 1979" (1979 B brochure). The press record year by year is on the History page.
Sources↑ TOP
- MX-5050B maintenance manual, OS2-004 — p.83 (the dc servo and synchronous model lists), p.17 Table 2-2 (speeds of the 2H, 2L and 4L), sections 2-4 and 2-6 (belt drive and direct drive). The scan is at /manuals/otari-mx5050b-maintenance-manual-os2-004.pdf.
- Recording Engineer/Producer, August 1978 — the earliest B advertising found, at $1,795.
- MX-5050-B brochure, 107-9-79 — the September 1979 date, the standard DC capstan servo and the operating position.